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Objective To establish the risk index of early-warning on the human infections with avian influenza A (H7N9) virus. Methods The risk index (X) was calculated by using Principal Component Analysis based on the surveillance results (including the positive rates of environmental specimens and premises) during the period from April 2013 to March 2017 in Zhejiang Province. Then, the method of Classification and Regression Trees was used to establish the early-warning model for forewarning the epidemic situation of H7N9 human infections. Results The weights of two rates (the positive rates of specimens and premises) used to establish the risk index were 0.0545 and 0.0230 respectively. In the model of Classification and Regression Trees, risk index was divided into 4 grades: X ≤0.140, 0.140<X ≤0.757, 0.757<X ≤3.285 and X>3.285. Compared to the 1st grade, the risk ratios of the 2nd, 3rd and 4th grades were 7.4, 21.7 and 29.9 respectively. The accuracy, sensitivity and specificity of prediction were 86.1％ , 80.8％ and 87.3％ respectively, and the Kappa value was 0.592 . Conclusion The established risk index can be used to forewarn the H7N9 human infections, which is helpful for emergency preparedness and disease control.
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In order to analyze the temporal distribution characteristics of human rabies in China and explore the incidence forecasting,R3.3.2 software were used to establish the optimal ARIMA model of monthly incidences from 2004 to 2015 in Chi-na.Then the monthly incidences from January to November 2016 were forecasted with the model and the prediction accuracy was evaluated.The annual incidences of human rabies in China were decreasing tendency since 2007,and the monthly incidence reached highly during August to October.The optimal model was ARIMA(2,1,1)(2,0,0)12and the mean absolute error (MASE)was 0.755.The mean relative error was 15.61% when predicting the incidences from January to November 2016.In conclusion,there exists seasonal variation for human rabies in China and ARIMA model can be applied for the short-term fore-casting.
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Objective To provide evidence for effective implementation of influenza and pneumonia immune strategies, we investigated the awareness of influenza and pneumonia and the willingness of vaccination among chronic disease patients.Methods A stratified multistage cluster sampling method was used to investigate 720 patients less than 75 years of age.Results Overall, 717 completed responses were received.The awareness rates of influenza and pneumonia diseases were 59.83% and 59.55%, respectively.However, the awareness rates of influenza and pneumonia vaccine were 17.71% and 6.00%, respectively.The vaccination rate of influenza vaccine was 1.26% while no patients received pneumonia vaccination.Among those not vaccinated the most frequent reasons for not receiving the vaccine included "Believed oneself unlikely to be infected with influenza/pneumonia" and "No recommendation has been received for influenza/pneumonia vaccination".The influence on recommendations by doctors at vaccine clinic and by general practitioner had no significant statistical difference (P>0.05).Conclusion The main reasons for such low awareness and willingness may be due to their poorly knowledge on the risk of influenza/pneumonia diseases, and related vaccines.Health education and intervention should be taken to heighten the vaccination rates of influenza/pneumonia vaccines.
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Objective To learn the timeliness and reasons for the delay in discovering outbreaks via a dengue fever outbreak in Zhejiang Province,and try to improve our disease monitoring system.Methods Epidemic and clinic data were collected by searching cases and epidemiological investigation,and clinic behavior of cases in dengue fever outbreak were described,then the risk factors involved in the delay in discovering outbreak were analyzed.Results Totally 46 cases were found in this outbreak,among which 36 (78.28％) cases were infected before.The onset date of the first case we found was on July 15 th,57 day before the outbreak confirmation.According to the results,95.65％ of cases see a doctor after their sickness,and the rate of three day hospital visiting was 93.36％ (42/46),among which the rate of three day hospital visiting before pathogen confirmation was 91.67％ (33/36),and there was no statistic significance in diagnostic rate before and after pathogen confirmation(P =1.00).Conclusion Cases in this dengue outbreak presented high and timely outpatient rate.Thus,the delay confirmation of dengue fever outbreak was caused by the low sensitivity of doctors in all levels of hospital.More training on dengue fever diagnosis for doctors should be carried out in the future to control and prevent dengue fever more efficiently.
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Objective To evaluate epidemiological capacity of infectious disease in institutions of disease control and prevention,and to improve the ability of infectious disease control and prevention. Methods Questionnaires of epidemiological capacity of infectious disease evaluation in institutions of disease control and prevention which contained surveillance analysis,emergency response,plan system and so on were used to evaluate epidemiological capacity of infectious disease in all of city,district or county level of center for disease control and prevention in Ningbo,Shaoxing, Quzhou.The degree of attainment for the ability or (and)resources was divided into vary bad,bad,average,and good. Descriptive epidemiological methods were used to perform analysis and evaluation.Results The capability for monitoring notifiable infectious diseases reaching to good was 1 9 (76.00%),greater than that in non -statutory communicable diseases 2 (8.00%). Twenty four (96.00%) institutions reported that the most important factor limiting the epidemiological capacity of infectious disease was lack of human resources,and 20 (80.00%)of institutions supported infectious disease epidemiology staff to publish articles in academic journals,but scientific research ability reaching to good was 3(1 2.00%).Training subordinate institution capacity reaching to good was 1 0(40.00%),with 2 (8.00%)reporting very bad.Most abilities were not significant across different regions,only significant in non -statutory communicable diseases surveillance (χ2 =7.04,P =0.03).Conclusion Institutions of disease control and prevention had a certain epidemiological capacity of infectious disease,and almost balance in different regions.For further enhancing the ability,it is necessary to increase the number of personnel,and to improve the ability of education and training.
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Objective ToinvestigateanimportedcaseofZikavirusdiseaseinWenzhouCity,toexplorethesourceof infection,to analyse the problems during surveillance and diagnosis,and to provide evidence for prevention and control of Zikavirusdisease.Methods Byfieldinvestigation,medicalrecordsofthepatientwerecollectedandaface-to-face interview was conducted;blood,urine and saliva samples within 48 h were collected for RNA detection;assess the risk of diseasespreadingbymosquitosurveillanceandtakecontrolmeasures.Results Theonsetofthediseasewasonthepatient's way home from aboard on February 21st,2016.Before then,She lived in Paramaribo,the capital of Suriname in South America,which is an epidemic area of Zika virus.The patient had exposure history,with red,diffuse rash on her head,face, neck and limbs,and once was diagnosed as allergic eruption because of no fever.The two blood samples were both tested negative yet We detected urine and saliva samples showed positive.With the evidence above,the patient was finally diagnosed as an imported Zika virus case.The spreading risk of this case was low due to the low temperature.Conclusion there may be cases without fever or with blood sample tested RNA negative.As the weather gets warmer,missed diagnosis should be aware of,or the risk of spreading through mosquitos would increase.Therefore,in order to further improvement should lie in mosquito control and disease surveillance.
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Objective To learn the immunity level of Neisseria meningitides (Nm) serogroup W1 35 among healthy population.Methods A total of 410 children aged 0 -14 years were selected by stratified random sampling method in Zhuji city.The polysaccharide antibody IgG level of Nm serogroup W1 35 was detected by ELISA.The antibody concentrations more than 2 μg/mL were identified as positive.Results The geometric mean concentration (GMC)was 1.46 ±0.25 μg/mL and the W1 35 -antibody positive rate was 4.63%.There was no difference on antibody GMC and the W1 35 -antibody postive rate among different region and gender groups.There were statistical differences on antibody GMC among different age groups (P<0.05).The antibody GMT in the age group 15 -34(1.63 ±0.28 μg/mL )was significantly higher than that in other age groups(P <0.05),and the antibody GMT in the age group 1.5 -4 (1.37 ±0.19 μg/mL)was significantly lower than that in the age group 5 -14 (P <0.05).The antibody GMT were significantly lower in the elderly (≥60 years old)than that in the age group <10 and 5 -14(P <0.05).Conclusion The immunity level of Nm serogroup W1 35 among healthy population is low,and it is suggested to be immunized by the vaccines which contained Nm W1 35.
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Objective To learn the status of human resources of vaccination clinics in Zhejiang province and to give suggestions for optimizing the allocation.Methods Investigation and the focus group interview were conducted in Zhejiang Province to learn the configuration standards in vaccination clinics.Results The mean number who attended the immunization work every vaccination day in those clinics was five.The number of staff in each clinic differed from county to county but all reached 0.9 persons serving for 10,000 residents.There should not be less than four persons in each vaccination clinic theoretically.It should be necessary to increase one vaccination staff in every 50 injection doses of vaccine workload.Conclusion The staff of vaccination clinics is inadequate and unbalanced in Zhejiang Province.We should increase staff numbers according to workload and served population.
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Objective Toinvestigatethestatusoftick-borneRickettsiaeinfectionsamongmurine-likeanimalsin differentareasofZhejiangprovince.Methods Liverandspleensamplesofmurine-likeanimalscapturedthroughnight trapping method were collected from Anji,Jinhua and Tiantai County according to their geographic locations and historical detection of Rickettsiae .Nest-PCR tests were used to determine the presence of the 16S rRNA genes of Anaplasma and Ehrlichia ,and the heat shock protein genes (groEL)of Rickettsiae (including typhus and spotted fever group)and Orientiainthesesamples.Results Atotalof851murine-likeanimalsbelongingto14specieswerecaptured.The predominant species were Rattus confucianus (30.32%),Apodemus agrarius (18.80%) and Thallomys paedulcus (1 1.75%)and they were significantly different among three areas (P<0.05 ).48 Rickettsia positive were found in 562 tested samples with the positive rate of 8.54%,among which the percentage of Anaplasma,typhus group Rickettsia, Orientia,Ehrlichia and spotted fever group Rickettsia were 3.38%,1.78%,1.78%,1.07% and 0.53% respectively. The positive rates of Anaplasma in Jindong (4.76%)and Anji (4.27%)were significantly higher than that in Tiantai (P<0.05 )while the spotted fever group Rickettsia were found only in Tiantai County.Moreover,Rattus confucianus-the predominant species of Zhejiang Province-had the highest infection rate of tick-borne Rickettsiae up to 14.97%.Co-infections with several Rickettsiae were existed among the same species.Conclusion Rickettsiae infections exist widely among different areas of Zhejiang province and the positive rates are significantly different among species.
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<p><b>OBJECTIVE</b>To explore the clinical spectrum, geographic location of human H7N9 avian influenza as well as the characteristics of population at high risk of infection, in order to develop strategies for the prevention and control of the infection. Clinical and epidemiological characteristics on the 6 confirmed human cases in Zhejiang were also analyzed.</p><p><b>METHODS</b>Real-time fluorescent quantitative PCR was used to test the nucleic acid of human H7N9 avian influenza infection, from pharyngeal swabs of the patients and their close contacts. Face to face interview and descriptive method were used to collect related clinical and epidemiological data. Statistical analysis was performed by SPSS 17.0.</p><p><b>RESULTS</b>Six confirmed cases were distributed in Hangzhou and Huzhou cities. The 6 confirmed human cases, including 5 males and 1 female were all confirmed with novel influenza A (H7N9) virus infection, with an average age as 60.83 years (with median as 64.50 years). Cough was the most common initial symptom to be noticed. The clinical manifestations would include fever, dizziness, pain of muscles, coughing, expectoration and short of breath. All the X-ray chest films showed severe pneumonia, and 5 of them having had other chronic diseases. None of the cases admitted to have had a history of exposure to ill/death avians. However, all of the cases had been frequently exposed to the agricultural-byproduct-trading-markets where the positive rate of novel influenza A (H7N9) virus in environmental specimens was up to 43.21%. 32 of the 375 close contacts (8.53%) to the 6 cases appeared abnormal symptoms, but no positive result related to novel influenza A (H7N9) virus nucleic acid was detected from their throat swabs.</p><p><b>CONCLUSION</b>Acute infection on the respiratory system seemed the main clinical manifestation. Elderly men, especially those with chronic diseases were under high risk of human infection with H7N9 avian influenza. The source of infection might be associated with the exposure to poultry. There was still lack of evidence to confirm the route of person to person transmission on H7N9 avian influenza.</p>
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Adult , Aged , Female , Humans , Male , Middle Aged , China , Epidemiology , Influenza A Virus, H7N9 Subtype , Influenza, Human , Epidemiology , VirologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the coverage rate of primary immunization of measles containing vaccine (MCV1) among migrant children in Yiwu,Zhejiang province.</p><p><b>METHODS</b>Household cluster sampling survey and probability proportion to size sampling method were adopted. A total of 967 migrant children born from 1st July 2007 to 1st July 2010 and their caregivers were selected as target population. Standard face-to-face interviews were conducted to investigate the subjects' knowledge, attitude, practice (KAP) of immunization, MCV1 vaccination and determinants. Multi-variable weighted average score method was adopted to evaluate the result of our survey on KAP. Kaplan-Meier analysis was adopted to assess the coverage of MCV1 and Cox regression analysis was adopted to explore the influencing factors associated with the coverage of MCV1.</p><p><b>RESULTS</b>Out of the 967 children, 104 were born in 2007, accounting for 10.8%; 301 were born in 2008, accounting for 31.1%; 343 were born in 2009, accounting for 35.5% and 219 were born in 2010, accounting for 22.6%. Among the surveyed caregivers, 71.9% (695/967) were mothers and 90.2% (872/976) were migrant from other provinces. According to the result of survey on KAP among caregivers, 56.2% (543/967) scored ≥ 4 points on knowledge, 75.8% (734/967) scored ≥ 4 points on attitude and 48.7% (471/967) scored ≥ 4 points on behavior. 86.6% (838/967) of surveyed caregivers' education levels were under junior middle school.85.9% (831/967) of the migrant children were born in hospitals.36.3% (351/967) of the surveyed families' household income were under 2000 yuan per month.32.7% (316/967) of surveyed caregivers waited less than 15 min for immunization for each time. Coverage rate of MCV1 was 85.9% (831/967; 95%CI: 83.7%-88.1%). The timely coverage rates at 8 months, 12 months, and 24 months were 58.8% (569/967; 95%CI: 55.5%-62.1%), 88.2% (853/967; 95%CI: 86.0%-90.4%) and 98.6% (953/967; 95%CI: 97.8%-99.4%), respectively. The average age of MCV1 immunization for each birth cohort between 2007 and 2010 were 10.4, 10.1, 10.1 and 9.3 month, respectively; without statistical significance (χ(2) = 0.722, P = 0.398). According to the analysis by Cox regression, the caregivers aged ≤ 25 years (24.3% (235/967), RR = 1.520 (95%CI: 1.280-1.800)), the caregivers' education level above college (2.8% (27/967), RR = 3.841 (95%CI: 2.287-6.451)), delivered in county-level hospital (49.4% (478/967), RR = 6.048 (95%CI: 4.311-8.485)), household income > 4000 yuan per month (21.7% (210/967), RR = 1.366 (95%CI:1.163-1.604)), the average score of attitude towards immunization ≥ 4 points (75.9%(734/967), RR = 2.613 (95%CI: 1.026-6.655)), the average waiting time for each vaccination ≤ 15 min (32.7% (316/967), RR = 2.116 (95%CI: 1.341-3.339)) were the important factors to improve the timely immunization coverage rate of MCV1 among migrant children.</p><p><b>CONCLUSION</b>The coverage of MCV1 were obviously delayed among migrant children in Yiwu, Zhejiang province. We suggest that the investigation of migrant children should be strengthened and remind or recall mechanism for immunization should be established. Increasing the open days for immunization clinics and reducing the waiting time for vaccination could also improve the coverage and timeliness of the MCV vaccination.</p>
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Child , Child, Preschool , Female , Humans , Male , China , Family Characteristics , Health Knowledge, Attitudes, Practice , Measles Vaccine , Regression Analysis , Transients and Migrants , VaccinationABSTRACT
Objective To evaluate the epidemiological effects of vaccine immunization program related to A(H1N1)influenza in the middle school students.Methods Non-randomized clinical trial was designed to assess the A(H1N1)influenza vaccine on its efficacy.14883 students from 8 middle schools in Zhejiang province were recruited and classified into vaccinated or control groups,based on the status of immunization with A(H1N1)influenza vaccine.All subjects were followed up through one epidemic period(6 months)and the incidence rates of influenza-like illnesses,A(H1N1)influenza,and seasonal influenza in these two groups were compared to evaluate the efficacy of the vaccine.Results There were 6334 subjects in the vaccinated group and 8549 in the control group.7441.75 person-years were followed from these two groups.The incidence rate of A (H1N1)influenza in vaccinated group was 1.64‰ per person-year,lower than that of the control group.The rate difference(RD)was-1.64‰ per person-year(95% confidence interval value from-3.04‰ to-0.23‰ per person-year),and the difference was significant(P=0.010).The incidence rate of influenza-like illnesses in vaccinated group was 21.47‰ per person-year,lower than that of the control group(22.69‰ per person-year)and the diffefence was not significant(P>0.05).The incidence rate of B influenza in vaccinated group was 6.63‰ per person-year,higher than that of control group(7.02‰ per person-year)but the difference was not significant(P>0.05).Conclusion This vaccine demonstrated a good epidemiological effect against the A(H1N1)influenza virus infection,observed through a student-immunization program.The cross-protection effect against the influenza-like illnesses and other seasonal influenzas was not noticed in this study.
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Objective On July 6, 2010, the parents of a patient with confirmed measles reported several suspected measles patients with fever and rash in their village. An investigation was carried out to verify and understand the cause of the outbreak. Methods Several suspected cases had an onset of fever and rash in this and other neighboring villages during June 1 to August 3,2010. A confirmed case was a suspected case with measles-specific IgM identified in the serum. We conducted door-to-door visits and searched the Chinese Center for Disease Control and Prevention Information System to identify cases, also conducted a retrospective cohort study among migrant children aged 8 months-14 years to identify risk factors related to measles. Results We identified 19 measles cases (17 confirmed case, 2 suspected cases)in the village, and all of them were migrants. Children aged 1-2 years had the highest attack rate(13%). The primary case-patient had onset on the day she arrived in this village(June 4,2010). Caretakers from an unlicensed private clinic were providing service in the village but did not report the outbreak to the public health authority. The outbreak was identified only after receiving a report from the parents of one of the patients, by that time the outbreak had lasted for one month. The measles vaccine coverage rate was 81% among the 315 migrant children aged 8 months-14 years. Among the 61 unvaccinated children, those who reportedly being contacted a measles patient had a higher attack rate(14/16, 88%)than those who did not(2/45, 4.4%)(Relative risk=20, Fisher' s exact 95% confidence interval: 5.7-94). Conclusion The low measles vaccine coverage among migrant children and lack of measures taken on the incident, timely isolation diagnosis/reporting by the caretakers from the unlicensed private clinic etc. had contributed to this prolonged outbreak. Measures need to be taken to improve the immunization services for migrant populations and to enhance measles surveillance programs in the area.
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<p><b>OBJECTIVE</b>To explore the relation between hepatitis B virus DNA load and genotype with the level of large envelope protein.</p><p><b>METHODS</b>Serum HBV DNA was quantitively detected by using real time polymerase chain reaction (RT-PCR). The LHBs were detected by using enzyme linked immuno sorbent assay (ELISA) and HBV markers were detected by time differentiate immunofluorescence assay in 140 serum samples collected from chronic hepatitis B patients.The genotypes of HBV were identified by DNA sequencing; and analyze their relationship.</p><p><b>RESULTS</b>There was no significant difference between positive rate of LHBs and that of HBV DNA in HBeAg negative and positive group (P > 0.05); The HBV LHBs absorbency was markedly correlated with the HBV DNA load ( R2 = 0.9267). The difference of HBV LHBs absorbency between HBV genotype B and C was not significant.</p><p><b>CONCLUSIONS</b>The close correlation between HBV LHBs absorbence and HBV DNA load illustrated that he level of serum LHBs can be used to estimate the state of HBV replication; and there is no relationship between HBV LHBs absorbency and genotypes. So HBV LHBs may be used as a new serological marker to detect HBV replication.</p>
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Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , DNA, Viral , Genetics , Allergy and Immunology , Enzyme-Linked Immunosorbent Assay , Genotype , Hepatitis B , Genetics , Virology , Hepatitis B virus , Chemistry , Genetics , Reverse Transcriptase Polymerase Chain Reaction , Viral Envelope Proteins , Chemistry , Genetics , Virion , Chemistry , GeneticsABSTRACT
Objective To identify the presence of candidate pathogenicity island 89K DNA sequence of Streptococcus suis serotype 2 (SS2) strains isolated from patient in Zhejiang province. Methods Genes and DNA fragments were amplified by PCR, using specific primers, and three amplified fragments of the89K sequence were directly sequenced. The results were analyzed using software related to bioinformaties and epidemiology. Results 8 strains of SS2 all contained 89K sequence, cps2J and mrp virulent genes, and species-specific 16S rDNA. 3 amplified fragments of 89K candidate pathogenicity island of SS2 ZJ0501 were above 99% similar to SS2 strain identified from outbreaks in Jiangsu in 1998, and the gene fragment of coding DNA recombinant protein in the 89K sequence was highly homological with that of S. dysgalactiae and S. agalactiae. Conclusion In recent years SS2 strains isolaed from patients with clinical symptoms in Zhejiang province had been detected to have contained candidate pathogenicy 89K DNA fragment.
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<p><b>OBJECTIVE</b>To evaluate the epidemiological and serological efficacy after 10 years of vaccination against hemorrhagic fever with renal syndrome (HFRS) vaccines in Zhejiang province.</p><p><b>METHODS</b>One county was randomly chosen as the research unit with all the healthy people between 16 and 60 years old were equally divided into study and control groups. The study group was vaccinated. Immunofluorescent antibody assay was used to test specific IgG antibody and Mcro-CPE method was used to test the titer of neutralizing antibody.</p><p><b>RESULTS</b>Two weeks after the full-course immunization, the seroconversion rate became 100% (67/67, with 95% CI as 96.3%-100%) by immunofluorescent antibody test (IgG) and 44.4% (8/18 with 95% CI as 22.0%-69.0%) by neutralization test with GMT titers as 72.1 and 4.6 respectively. Booster immunization was provided one year later. Time span as two weeks prior to, one year, one and half years, two years, three years and five years after booster immunization, the rates of seroconversion on immunofluorescent antibody using IFAT method, were 28.6%, 83.3%, 75.0%, 53.1%, 22.6%, 10.0% and 55.0% respectively, and rates of seroconversion of neutralizing antibody by Mcro-CPE method were 14.8%, 55.6%, 35.0%, 31.3%, 26.0%, 10.0% and 50.0% respectively. Nine years after the reinforcement, the rates of seroconversion of immunofluorescent antibody by IFAT method was only 7.1%. The vaccinated group had no patient seen but the control group appeared 34 patients including 3 deaths. According to the ten-year observation, the vaccine seemed effective with the protection rate in population reached 100%.</p><p><b>CONCLUSION</b>HFRS vaccine was effective on epidemiological, social and economical efficacy.</p>
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Adolescent , Adult , Animals , Female , Humans , Male , Middle Aged , Rats , Young Adult , Hemorrhagic Fever with Renal Syndrome , Epidemiology , Allergy and Immunology , Immunization, Secondary , Methods , Vaccination , Methods , Viral Vaccines , Therapeutic UsesABSTRACT
<p><b>OBJECTIVE</b>To examine vibrio cholera (V.C) in aquatic products of littoral area, Zhejiang Province and to provide scientific evidence for administration of aquatic products and cholera epidemic control.</p><p><b>METHODS</b>All 990 samples of aquatic products collected from local markets, eateries and aquafarms in three chosen areas. Samples were proliferated in alkaline liquid medium, and purified in NO: 4 medium, the isolations were identified biochemically, and phenotype of strains were defined by phagocyte and coagulation with V.C. diagnostic serum. Three virulence genes (ctx, ace, zct) of the isolated strains were detected by polymerase chain reaction (PCR).</p><p><b>RESULTS</b>There were 1.41% samples caught by V.C., having a carrying rate highest in turtles of 8.9%. 14 strains were defined as three serogroups, and the numbers of Inaba, Ogawa, and Hikojima types were 2, 2, 10 respectively. Virulence genes had detected in 9 of 12 stains. All genes were detected in 5 strains, only ZOT genes in 3 strains, and both CTX and ACE genes in 1 strain.</p><p><b>CONCLUSIONS</b>Aquatic products from inshore in Zhejiang Province caught with V.C. strains might be divided into three serogroups. Most of them should be virulence genes. Cholera epidemic outbreak might be caused by those contaminated products.</p>
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China , Food Microbiology , Genes, Bacterial , Seafood , Microbiology , Vibrio cholerae , Genetics , Virulence Factors , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To observe the serological and epidemiological efficacy of hemorrhagic fever renal syndrome (HFRS) vaccine in Zhejiang province.</p><p><b>METHODS</b>Immunofluorescent antibody assay and Mcro-CPE method were used to test specific IgG antibody and the titer of neutralizing antibody.</p><p><b>RESULTS</b>Two weeks after the injection of the third dose, the sero-conversion rates by both immunofluorescent antibody test (IgG) and neutralization test were 100.0% (67/67) (95% CI: 96.3 - 100.0) and 44.4% (8/18)(95% CI: 22.0 - 69.0) with geometric mean titers (GMTs) 72.1 and 4.6 respectively. The rates of seroconversion of immunofluorescent antibody by immunofluorescence antibody assay (IFA) were 28.6%, 83.3%, 75.0%, 53.1%, 22.6%, 10.0% and 55.0% before reinforcement, two weeks, one year, one year and a half years, two years, three years and five years after reinforcement. The rates of neutralizing antibody seroconversion by the Mcro-CPE method were found as 14.8%, 55.6%, 35.0%, 31.3%, 26.0%, 10.0% and 50.0% respectively. We found some antibody dependent immunization enhancement phenomenon among the inoculated population, but further observation was needed.</p><p><b>CONCLUSION</b>HFRS vaccine was immunologically effective and the duration of serous antibody last long.</p>